In a study that included 3001 patients with all subtypes, the DFS of Her-2 positive subtype in the IDC-DCIS group was better than that in the IDC group, while there was no significant difference in DFS between the two groups in patients with triple negative molecular subtypes, which may be related to the small sample size of triple negative IDC-DCIS patients (Goh et al. 2019). The gene discussed is ERBB2; the disease is ductal breast carcinoma in situ.